Weft detecting mechanism for looms



w. H. BAHAN WEFT DETECTING MECHANISM FOR LOOMS Filed Nov. 16, 1939 VV/LL/AMH. BAHAN Imnentor attorney filling detector means, upon Patented Dec. 24, 1940 PATENT OFFH'ICE WEFT DETECTING MECHANISM FOR LOOMS William H. Bahan, Greenville, S. 0. Application November 16, 1939, Serial No. 304,799

2 Claims.

This invention relates to a weft detectin mechanism for looms and more especially to an improved type of grid which forms a part of this mechanism.

Practically all looms in use are provided with means for stopping the loom when the filling becomes broken, and in case of automatic looms, means are provided for replenishing the filling supply in the shuttle upon the exhaustion of the filling on the bobbin in the shuttle. In some types of' looms there are no means for automatically replenishing the filling supply when it becomes exhausted but stop motions are used to detect this failure of the filling to stop the loom so that the operator can replenish the filling supply. In other types of looms, such as battery looms, magazine looms and the like, the the exhaustion of the filling supply in the shuttle, automatically operates the filling replenishing means to place a new supply of filling in the shuttle. The improved detector grid shown in the accompanying drawing is adapted to work on both types of looms, so that an automatic loom will have its filling carrier changed upon the parting of the filling before exhaustion.

In filling detectors heretofore employed, much dificulty has been encountered due to accumulation of lint, fiy and the like, upon the grid bars thus preventing the feeler fork from actuating the loom stopping mechanism 'or re plenishing mechanism due to the'fa'ilure of the filling fork to pass between the grid bars when a weft thread becomes broken or is absent. This failure on the part of the feeler mechanism results in thin places in the cloth. One of the causes of this lint accumulation has been the tendency of the wooden lay upon which the grid is mounted to absorb moisture and thus present a cohesive surface for collecting lint in'the path of the feeler fork and between the grid bars. Since the lower ends of the feeler fork prongs are disposed in close proximity to the lay during its reciprocation, towards and away from the fork, the lint upon a wooden lay will soon be moved against thegrid bars so as to prevent the prongs from moving therebetween when a filling thread is absent or becomes broken.

It is therefore anobject of this invention to provide a combined feeler grid and ametallic plate, which plate is secured in a transverse groove in the top of the lay directly below the path travelled by the prongs of the feeler fork so that a smooth non-cohesive and moisture proof surface will 'be present below the feeler fork and the grid bars. By having this type ofsurface, lint and foreign matter will not accumulate, but instead the motion of the lay back and forth relative to the feeler fork will produce sufficient air currents to keep the loose particles 5 removed.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawing, in which-- Figure 1 is a perspective view of a portion of a loom showing my improved grid bar associated therewith;

Figure 2 is an isometric view showing the improved grid bar and a fillingfeeler fork pressing a taut strand of filling into engagement therewith; s

Figure 3 is an isometric view of a portion of a loom lay showing a slightly modified form of feeler grate mounted thereon;

Figure 4 is an isometric view of still another modified form of grate shown in association with a filling feeler fork the strand of filling being absent. I

Referring more specifically to the drawing, the numeral 10 denotes a conventional loom lay which is usually made of wood. This lay has installed therein intermediate its ends, a conventional reed ll. Also a shuttle box [2 is disposed on each end, only one being shown. This shuttle box is adapted to receive a suitable shuttle I4 having a filling strand I5 emanating therefrom. During the operation of the loom, the shuttle I4 is projected back and'forth along the shuttle race portion 25 of the lay and between sheds I6 and I1 so that cloth l8 will be woven in a well known manner. Of course, each time the shuttle moves between the sheds l6 and H, a suitable harness mechanism, not shown, serves to reverse the position of the warp ends to form 40 new sheds and then when the shuttle is again passed between the sheds, the lay moves towards the observer to cause the newly inserted filling to be pressed against the woven fabric i8.

Means are provided for automatically stopping the loom when the filling becomes absent or for automatically replenishing the filling when it becomes exhausted or broken. This is accomplished by a suitable feeler mechanism comprising a grate l9 which is formed from one continuous wire bent upon itself, in a substantially U-shaped manner and inverted with its lower ends being secured to the upper surface of an L-shaped metallic plate 2|. In order to provide the proper space between the grid wire,

the upper portion thereof is again bent as at 20 toward the back side of the lay. This L- shaped plate is adapted to fit in the base of a notch 22 cut in the top of the lay 10. The downstanding leg 21a of the L-shaped plate 2| fits against one side of the lay and has a hole 23 therein which is penetrated by a wood screw 24 to securely hold the plate in position. The top surface of the plate 2| is preferably polished so that the surface will not have a tendency to cause lint, dust and the like to accumulate thereon.

The grate l9 has shoulder portions 26 a short distance above the plate 2 I The purpose of these shoulder portions is to act as a stop for the filling thread I to retard its upward movement when this thread is moved into engagement with the grid 20 by feeler fork prongs 21 in the manner shown in Figure 2. It will be notedin this figure that the filling bar [5 has been pushed between the grate bars. Penetration of the spaces between the grid bars by the prongs does not usually occur except when the filling becomes broken or exhausted. Normally the filling it? will remain substantially taut and prevent the prong 27 of the fork from penetrating the space between the grate.

The lower ends of the fork prongs are disposed only a slight distance above the top of the plate 2!; therefore, as the lay reciprccates back and forth-toward and away from the fork, the air currents set up by the lower ends of the prongs will serve to fan any loose particles out of the path and thus keep the area between the grate and the fork free from any obstructions which might cause the grate to become clogged.

The fork prongs 21 extend downwardly from block 23 which, in turn, is adapted to be pivoted as at 29 to a slide 33, said slide being mounted for sliding movement in the bracket 3 l. Bracket 3! is secured to a breast beam 32 by any suitable means such as a bolt 33. A looped wire 34 is secured to the block 23 at substantially right angles to the prongs 21. This loop is normally adapted to rest behind a snake head 35 in the manner shown in Figure 1, when the prongs 27 are not engaging a taut filling 55. The snake head 35 is pivoted as at 36 to a vertically disposed member 3? and this member together with the snake head, reciprocates back and forth longitudinally to the slide. When the lay Ill with the filling i5 moves toward the observer in Figure 1, the filling 55, if taut, prevents the prongs 27 of the fork from penetrating the space between the U-shaped grid wire iii. The obstruction offered by the filling strand l5 will cause the fork to rotate in a counter-clockwise manner about pivot point 29 and thus move the loop 34 out of engagement with the snake head 35. As a result, the memhere 35 and 31 will move toward the observer while the fork prongs engage the filling, and the snake head 35 will slide beneath the loop 3d and not engage the same. Onthe other hand when a filling becomes absent to allow the prongs 21 to penetrate the grid is as shown in Figure 4 then upon the beat up of the lay, the feeler fork will not be rotated and consequently the loop 34 will remain in a position where the hook on snake head 35 will engage the same, and then upon its travel toward the observer in Figure 1, the entire slide 30' will be moved.

This slide has a pivoted dog 53' secured thereto, the free end of which is disposed in close proximity to one end of a lever ll, said lever 4| being pivotally secured as at 42 to the breast beam 32. The other end of lever 4| is adapted to engage the side of a knock-off lever 43 which is disposed in a slot 44 of bracket 45 and resting against shoulder 46. When the slide 33 moves toward the observer, as in case of a filling [5 being absent or broken, the dog 40 will rotate the lever 4| to also cause the upper end of knockoff lever 43 to move out of engagement with shoulder 46 and into slot 45, thus allowing the lever to rotate toward the observer by a suitable mechanism not shown and stop the loom.

In some instances it is necessary to actuate a filling replenishing mechanism without stopping the 100111. In such a case, the dog 40 is rotated upwardly by a conventional mechanism, not shown, so that its: free end will not engage the 'lever 4| to stop the loom, but as the slide 38 moves toward the observer in Figure 1, its end will engage the upper end of a lever 48 on shaft 49. When this shaft is rotated, it operates the filling replenishing mechanism to cause afilled bobbin to be transferred from the magazine to the shuttle.

Figure 3 shows a slightly modified form of the invention in which like reference characters will. apply to like parts with added reference characters usedto designate the difference. In this form the lay Ill has a substantially U-shaped plate 52 disposed in the slot in the top of the lay. This U-shaped plate hasa downstanding leg 53 integral therewith which fits againstthe back side of the lay and which is penetrated by a screw 54 for securing the plate in position. The upper surface of the plate 52 has the inverted U-shaped grid wire [9 extending upwardly therefrom as in the preceding form. It i's'here seen that the walls as well as the bottom of the groove in the top of the lay are covered to present a surface upon which lint and dust will not accumulate.

Figure 4 shows still another modified form of the invention'in which a plate 56 is shown having a downwardly extending leg 51 with a hole 53 therein which is penetrated by a suitableyscrew such as 24 when it is inserted in the slot 22 of' the lay l0. Secured to the upper side of the plate 56 is a continuous wire 59 which extends upwardly to points 60 'andthen b-ackwardly, forming aninverted combined U'-shaped and L-shaped member. The ends of the grid wire vare secured to the top of the plate 56. At a point on plate 55 midway the securing points for the ends of the wire 59, another wire BI is secured which extends upwardly substantially parallel to the legs of wire 59'and this wire is bent rearwardly as at 62 and has its upper ends secured to the intermediate portion of the wire 59. In other words, the grate in this form is identical to the grate shown in Figure 2, with the exception that three upstanding wires form the grate whereas in Figure 2 only twoupstanding wires areused. Suitable feeler prongs 65 are adapted-to penetrate the spaces between the grate bars as well as to press adjacent the opposed sides ofth'e outside grate wires. These prongs 65 extend downwardly from a block member 66 having a hole 67 therein which is used to pivortaily secure the same on the end of a slide suchas 3-D. Member 63 has a looped wire 68 extending therefrom at substantially right angles to the prongs and this loop is adapted to engage the'snake head 35 upon absence of a filling-l5 or upon the Same becoming broken. Likewise in this form the upstanding wires of the grid have shouldered portions" which are used to retard the upward travel of the filling l5 upon its engagement with the prongs 65 of the fork.

It is therefore seen that I have provided a very simple and efiicient filling grate which will prevent dust from accumulating on the top of the lay in the path of .the feeler fork. By keeping this pathway clear of foreign substance, the actuation of the feeler fork will be insured at the proper time thereby preventing the loom from operating several picks without placing any filling within the sheds.

Another very important feature in the present invention is the relationship between the number of grid bars and the number of prongs in the filling fork. The prongs in the grids, as has been stated, are reciprocated back and forth with the lay; whereas the prongs in the fork oscillate when a taut filling is present and remain substantially stationary when a filling is absent or broken. In each form, there is at least one more prong in the fork than there is in the grid. This will make the filling fork considerably more sensitive because less resistance is offered by the grate to the bending of a strand therebetween. For example, should the ends become broken substantially midway of the loom, a considerable amount of friction would be offered by the warp sheds, because the filling would have to be pulled longitudinally to allow the filling to be kinked between the grid bars in the manner shown in Figure 2. By providing a greater number of prongs in the filling fork than are present in the grid bar, the suspended weight of these prongs will be a factor in causing the broken strands to be properly kinked between the grid spaces so that the stop motion can be actuated.

In the drawing and specification, there has been set forth a preferred embodiment of the invention and although specific terms. are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the appended claims.

I claim:

'1. A loom lay having a transverse recess in the shuttle race portion thereof, a plate secured to the lay and covering the bottom of the recess, a grid rising from the plate, said grid comprising a continuous wire bent to inverted L-shape when viewed along a vertical plane transverse of the lay and presenting an inverted U-shape when viewed along a vertical plane extending longitudinally of the lay.

2. Aol oom lay having a transverse slot in the shuttle race portion thereof, a metallic plate covering the bottom and sidewalls of the slot, and a grid rising from the portion of the plate covering the bottom of the slot, said grid comprising a plurality of Wires joined together at their upper portions and Welded to the plate at their lower portions.

WILLIAM H. BAHAN. 

